“Do You Ever Wonder About… Invasive Fish in Pennsylvania?”
If you spend time around Pennsylvania’s lakes, rivers, or fishing spots, you might be surprised to learn that not every fish swimming in our waters actually belongs here. A handful of invasive fish species have found their way into the state, and they’re causing more trouble than you might expect.
These fish aren’t just visitors — they compete with native species, disrupt food chains, and can even change entire ecosystems.
Here are a few of the biggest troublemakers:
Northern Snakehead
A long, toothy predator that can breathe air and survive in low‑oxygen water. It eats just about anything and spreads quickly.
Round Goby
A small bottom‑dweller that steals food and habitat from native fish. It also eats the eggs of sport fish like smallmouth bass.
European Rudd
Often introduced accidentally through bait buckets. It breeds fast and changes plant life in ponds and lakes.
Ruffe
A tiny perch‑like fish that outcompetes native species for food.
Asian Carp (Bighead, Silver, Black)
Not established here yet — but close enough to worry wildlife officials. These carp can take over entire waterways if they get in.
Why It Matters:
Invasive fish can push out the species that make Pennsylvania’s waters special — from sunfish and perch to bass and trout. They also affect fishing, boating, and the overall health of our rivers and lakes.
What You Can Do:
Never release aquarium fish or leftover bait
Clean and dry boats and gear
Report unusual fish to the PA Fish & Boat Commission
Pennsylvania’s waterways are full of life — and keeping them healthy starts with knowing what doesn’t belong.
Carp Myths vs. Facts:
Myth: “Carp are native to Pennsylvania.” Fact: They’re not! Common Carp were brought here in the late 1800s — they’ve just been around long enough to feel like locals.
Myth: “Carp have always been part of PA fishing.” Fact: They became widespread by the mid‑1900s, so many of us grew up catching them and assumed they’d always been here.
Myth: “Carp don’t really affect the water.” Fact: They stir up mud, cloud the water, and pull up plants — small actions that make a big difference in a lake or river.
Myth: “Grass Carp are harmless because they’re sterile.” Fact: Today’s stocked Grass Carp are sterile, but older introductions weren’t. Even sterile fish can reshape a pond by eating too much vegetation.
Myth: “Asian Carp aren’t something we need to think about.” Fact: They’re not in Pennsylvania waters yet, but they’re close enough that wildlife officials keep a very close eye on them.
